Highway Traffic

I'm using L.S traffic which spawns the correct amount of cars I'm looking for but I have a problem on the highways. There are way too many cars spawning at a time and it even crashes my game in a few major intersections. I've been adjusting all the values hoping to find something that lets me control traffic only on the highway but so far these lines below are all that I see making some kind of changes (mostly PlayerRoadDensity) but it's taking way too much time. Does anyone know what exactly what these lines do? Or better yet, know of a way to solve my problem?